The present invention relates to an active matrix type liquid crystal color display unit used for office automation machines and computer terminal units.
As shown in FIG. 4, a prior art active matrix type multi-color display unit comprises a TFT substrate 2 having switching elements 8 and picture element electrodes 9, three primary color (R, G, B) coloring layers 3, light blocking layers 4 disposed in gaps between the coloring layers 3, a coloring layer protecting film 5 laminated on the coloring layers 3 and a color filter substrate 1 laminated thereon and comprised of a transparent electrode 6 which is a display common electrode. Liquid crystal 7, for example, is pinched between those two electrodes.
It has recently been desired to lower the resistance of the common electrode 6 of the active matrix type multi-color display unit to improve its picture quality. However, it is not easy to lower the resistance since the common electrode has to be a transparent electrode. Moreover, the transparent electrode has to be formed on the coloring layer which has no heat resistance, so that conditions for forming the film are restricted, rendering the lowering of the resistance more difficult.
Accordingly, it is an object of the present invention to solve the aforementioned problems and to obtain a high picture quality multi-color display unit by providing a low resistant common electrode.
It is another object of the present invention to provide low cost color electrooptical devices.